Idiopathic subglottic stenosis in pregnancy: A systematic review

Subglottic stenosis (SS) is a type of laryngotracheal stenosis defined by a location of less than 1.5 cm below the glottis or the vocal cords. Approximately 20% of cases are idiopathic.

We performed a systematic literature review of idiopathic subglottic stenosis (ISS) complicating pregnancy.

PubMed, Scopus, and clinicaltrials.gov databases were queried from inception through August 10, 2023 with the following terms: idiopathic subglottic tracheal stenosis, subglottic stenosis, subglottic stenoses, tracheal stenosis, tracheal stenoses, and pregnancy. This systematic review was conducted according to the methods described in the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines for reporting systematic reviews.

Studies detailing cases of ISS affecting pregnancy were included and studies reporting SS in pregnancy from a known etiology were excluded.

Our search identified 31 peer-reviewed published cases of ISS complicating pregnancy that met the inclusion criteria. We also included two additional cases from our institution. Publication bias was checked by the Joanna Briggs Institute critical appraisal tools. Descriptive statistical analyses were performed using Excel.

A majority of patients (26/33, 79%) were diagnosed with ISS during the reported pregnancy. Prior to pregnancy, 20/33 (61%) patients had a working diagnosis or reported symptoms of airway obstruction. Of these patients, 9/20 (45%) carried a diagnosis of asthma, and 6/20 (30%) carried a diagnosis of ISS. Specific symptoms prior to pregnancy were reported in 10/33 (30%) patients. The most common symptoms in these patients were dyspnea (10/10, 100%) and stridor (4/10, 40%). During pregnancy, all patients experienced worsening respiratory symptoms, with dyspnea (31/33, 94%), stridor (18/33, 55%), cough (13/33, 39%), hoarseness (7/33, 21%), and wheeze (5/33, 15%) being the most common symptoms. A total of 22/33 (67%) patients required medical and/or surgical management with dilation and/or excision during pregnancy. Postpartum outcomes were reported in 27/33 (82%) patients, and 1/27 (3.7%) required a tracheostomy immediately postpartum. The majority (18/27, 67%) of these patients required intervention postpartum, while 9/27 (33.3%) were asymptomatic.

ISS should be considered in pregnant patients with worsening respiratory symptoms despite medical management of asthma. If high clinical suspicion for upper airway obstruction exists, an otolaryngology referral for evaluation with bronchoscopy is recommended.